Question

In a certain triangle ABC , A equals 30°, B equals 50°, and the side AB equals 3 in. Use a protractor and a straightedge to construct the triangle. How many degrees should be in C? Measure this angle with your protractor. Does your measurement match your calculation?

Answer 1

If you were to compute this, Angle C should be equal to 100°.

In a triangle, all angles sum up to 180°.

In triangle ABC, where the m∠A =30° and m∠50°:

m∠A + m∠B + m∠C = 180°
30° + 50 + m∠C = 180°
80° + m∠C = 180°
m∠C = 180° - 80°
m∠C = 100°

The triangle should look like the picture attached.